fiddlesticks \FID-l-stiks\,
interjection:
(used to express impatience, dismissal, etc.)
"...If he had been an English lad, he would have been off to his sweetheart long before this, without saying with your leave or by your leave; but being a Frenchman, he is all for Aeneas and filial piety,—filial fiddle-sticks!"
-- Elizabeth Gaskell, "My Lady Ludlow," 1858
The lovers were fiddlesticks, he thought, collecting it all in his mind again. That's fiddlesticks, that's first-rate, he thought, putting one thing beside another. But he must read it again. He could not remember the whole shape of the thing.
-- Virginia Woolf, "To the Lighthouse," 1927
Fiddlesticks came to English in the 1400s from the late Middle English term fidillstyk.
Dictionary.com
